Impact of a Fermented High-Fiber Rye Diet on Helicobacter pylori and Cardio-Metabolic Risk Factors: A Randomized Controlled Trial Among Helicobacter pylori-Positive Chinese Adults

Abstract

<b>Background:</b> High dietary fiber intake has been associated with reduced risk of <i>Helicobacter pylori</i> infection and co-morbidities such as gastric cancer but also with reduced risk of cardiovascular disease. It has been suggested that fermented rye could affect <i>Helicobacter pylori</i> bacterial load and that high- fiber rye may be superior to wheat for improvement of several cardiometabolic risk factors, but few long-term interventions with high fiber rye foods have been conducted. <b>Objective:</b> To examine the effect of high-fiber wholegrain rye foods with added fermented rye bran vs. refined wheat on <i>Helicobacter pylori</i> infection and cardiometabolic risk markers in a Chinese population with a low habitual consumption of high fiber cereal foods. <b>Design:</b> A parallel dietary intervention was set up and 182 normal- or overweight men and women were randomized to consume wholegrain rye products containing fermented rye bran (FRB) or refined wheat (RW) for 12 weeks. Anthropometric measurements, fasting blood sample collection and ¹³C-urea breath test (¹³C-UBT) were performed at baseline and after 6 and 12 weeks of intervention as well as 12 weeks after the end of the intervention. <b>Results:</b> No difference between diets on <i>Helicobacter pylori</i> bacterial load measured by ¹³C-UBT breath test or in virulence factors of <i>Helicobacter pylori</i> in blood samples were found. Low density lipoprotein cholesterol (LDL-C) and high sensitivity C-reactive protein (hs-CRP) were significantly lower in the FRB group, compared to the RW group after 12 weeks of intervention. The intervention diets did not affect markers of glucose metabolism or insulin sensitivity. <b>Conclusions:</b> While the results of the present study did not support any effect of FRB on <i>Helicobacter pylori</i> bacterial load, beneficial effects on LDL-C and hs-CRP were clearly shown. This suggest that consumption of high fiber rye foods instead of refined wheat could be one strategy for primary prevention of cardiovascular disease. <b>Clinical Trial Registration:</b> The trial was registered at www.clinicaltrials.gov, Identifier: NCT03103386.